#!/usr/bin/env bash
# Shared helpers for release and PR title CI scripts.

SOURCE_DIR="python_repositories"

# Returns bump type (major|minor|patch) or empty if no valid prefix.
bump_type_from_title() {
  local title="$1"
  local lower
  lower=$(echo "$title" | tr '[:upper:]' '[:lower:]')

  if echo "$lower" | grep -qE '^\[(major|breaking)\]'; then
    echo "major"
  elif echo "$lower" | grep -qE '^\[(minor|feat)\]'; then
    echo "minor"
  elif echo "$lower" | grep -qE '^\[(patch|fix)\]'; then
    echo "patch"
  fi
}

title_has_bump_prefix() {
  [[ -n "$(bump_type_from_title "$1")" ]]
}

strip_bump_prefix() {
  local title="$1"
  echo "$title" | sed -E 's/^\[(patch|fix|minor|feat|major|breaking)\][[:space:]]*//i'
}

extract_pr_title_from_merge_commit() {
  local msg="$1"
  echo "$msg" | sed -n "s/^Merge pull request '\(.*\)' (#.*/\1/p"
}

changed_source_files() {
  grep -E "^${SOURCE_DIR}/" || true
}

has_source_changes() {
  local files="$1"
  echo "$files" | changed_source_files | grep -q .
}

read_pyproject_version() {
  sed -n 's/^version = "\(.*\)"/\1/p' pyproject.toml | head -1
}

latest_tag_version() {
  local tag
  tag=$(git describe --tags --abbrev=0 2>/dev/null || true)
  if [[ -n "$tag" ]]; then
    echo "${tag#v}"
  else
    read_pyproject_version
  fi
}

set_pyproject_version() {
  local version="$1"
  sed -i.bak -E "s/^version = \".*\"/version = \"${version}\"/" pyproject.toml
  rm -f pyproject.toml.bak
}

bump_semver() {
  local current="$1"
  local bump_type="$2"
  local major minor patch

  IFS=. read -r major minor patch <<< "$current"
  case "$bump_type" in
    major)
      major=$((major + 1))
      minor=0
      patch=0
      ;;
    minor)
      minor=$((minor + 1))
      patch=0
      ;;
    patch)
      patch=$((patch + 1))
      ;;
    *)
      echo "Unknown bump type: $bump_type" >&2
      return 1
      ;;
  esac
  echo "${major}.${minor}.${patch}"
}